SAN ANTONIO (AP) - Convicted hitman Charles Harrelson will get another crack at freedom when he appears in a federal courtroom today.

Harrelson, who received two life sentences for the contract killing of a federal judge in San Antonio nearly 20 years ago, is asking for a new trial. And this time, he has a legal dream team on his side.

Lawyers Bill May of Corpus Christi, David Michael of San Francisco and Alan Dershowitz - a Harvard law professor who represented O.J. Simpson - will ask U.S. District Court Judge Fred Biery to throw out his convictions. They'll argue Harrelson was railroaded by prosecutor misconduct and ineffective defense lawyers.

"He did not get a fair trial," Michael told the San Antonio Express-News in Sunday's editions. "Absolutely. Without a doubt.

"It's like George Orwell said, `It's the obvious that has to be continually restated.' "

Based on his pre-hearing affadavit, Harrelson will argue today - as he has all along - that he was 270 miles away in Dallas when U.S. District Judge John H. Wood Jr. received a fatal rifle blast to the back.

Another part of Harrelson's strategy apparently is to discredit a key witness who testified against him 16 years ago.

The courtroom drama is set to play out in Denver, near the Florence, Colo., Administrative Maximum Penitentiary, where the 59-year-old Harrelson has been held since trying to break out of an Atlanta federal prison in 1995.

The penitentiary, known as "Supermax" for its high security, is also home to Unabomber Ted Kaczynski; Soviet spy Christopher "Falcon" Boyce; World Trade Center bomber Ramzi Yousef; gang leader Luis Felipe, head of New York's Latin Kings; and Oklahoma City bomber Timothy McVeigh.

Harrelson's saga has all the drama of a film that could star his son, actor Woody Harrelson.

The actor, who was 7 years old when his father was convicted in 1968 of his first contract murder in South Texas, told Barbara Walters in a televised interview last year that his father didn't receive a fair trial in Wood's murder.

"I'm not saying my father is a saint, but I think he's innocent of that, yeah," the actor said on the eve of his Academy Award nomination for "The People vs. Larry Flynt."

The younger Harrelson won't say whether he's paying legal fees for his father, who described himself as "destitute" and "totally impecunious" in a 1996 Dallas Morning News interview.

Drug dealers hired Charles Harrelson to assassinate Wood the morning of May 29, 1979, as the jurist left his Alamo Heights townhouse.

The murder was a watershed in America's War on Drugs. Wood, known as "Maximum John" for his tough sentences of drug traffickers, was the first federal judge to be killed this century.

An investigation into Wood's death was bigger and more expensive than the investigation in the assassination of President John F. Kennedy.